CN101414646A

CN101414646A - A kind of new technique for manufacturing thin-film solar cell

Info

Publication number: CN101414646A
Application number: CNA2007100471141A
Authority: CN
Inventors: 倪党生; 叶曲波
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-10-17
Filing date: 2007-10-17
Publication date: 2009-04-22

Abstract

The present invention is for satisfying a kind of novel preparation process that solar cell market development needs design, the silicon slurry that utilizes silicon materials such as silico briquette, silicon chip to make is tied by physics barrel plating and sintering P-N, the preparation solar cell, enhance productivity, energy savings, the harm of conventional chemical sedimentation for environment has been avoided in environmental protection, effectively saved production cost, and it is simple and be easy to a promote technology again.This novel solar cell fabrication process adopts following technical scheme: the silicon slurry that silicon materials such as silico briquette, silicon chip are made is bonded in the substrate surface by physics barrel plating technology, sintering at high temperature, the surface silicon material infiltrates through 1～2 micron of substrate, again in conjunction with folded knot method and special surface treatment process, improve the suede effect of solar cell surface, strengthen light utilization, improve conversion efficiency.

Description

A kind of new technique for manufacturing thin-film solar cell

The present invention is for satisfying a kind of novel preparation process that solar cell market development needs design, the silicon slurry that utilizes silicon materials such as silico briquette, silicon chip to make is tied by physics barrel plating and sintering P-N, the preparation solar cell, enhance productivity, energy savings, the harm of conventional thin-film solar cells chemical deposition for environment has been avoided in environmental protection, effectively saved production cost, and it is a simple economy and the technology that is easy to promote again.

This novel solar cell fabrication process adopts following technical scheme: the silicon slurry that silicon materials such as silico briquette, silicon chip are made is bonded in the substrate surface by physics barrel plating technology, sintering at high temperature, the surface silicon material infiltrates through 1～2 micron of substrate, in conjunction with folded knot method and special surface treatment process, improve the suede effect of solar cell surface, strengthen light utilization, improve conversion efficiency.

Conventional solar cell preparation technology's flow process is mainly: one, and silicon substrate cleans, PVD deposition, making herbs into wool, lead-in wire, encapsulation; Complex process consumes a large amount of silicon materials, and uses a large amount of chemical liquids; Two, thin film silicon substrate solar cell is present emerging technology, and the substrate consume silicon is about one of original percentage, but still has complex process and consume the problem of a large amount of chemical liquids.The maximum characteristics of this novel solar cell fabrication process are not to be the chemical vapour deposition technique of routine, but prepare solar cell by high temperature sintering.Because this technology using method is simple relatively, cost is relatively low, the production lot flow process is easy to realize, do not produce chemical waste fluid, mating surface is handled can obtain high conversion rate, improve output rapidly, can satisfy the growth requirement of present solar cell industry, so can be used for substituting present common chemical vapour deposition process.Solar cell is the device that directly luminous energy is changed into electric energy by photoelectric effect or Photochemical effects.Thin-film type solar cell with photoelectric effect work is a main flow, solar irradiation is on the semiconductor p-n junction, form new hole-duplet, under the p-n junction effect of electric field, the hole flows to the p district by the n district, and electronics flows to the n district by the p district, just forms electric current behind the connection circuit, the operation principle of Here it is photoelectric effect solar cell, this process essence be: photon energy converts the process of electric energy to.

The technical matters of the novel barrel plating sintering method of the present invention is: the heatproof backing material is carried out surface treatment handle the formation matte, with the matte temperature-resistant material that disposes as substrate, under high temperature (temperature is higher than about 1410 degrees centigrade of silicon fusing points) condition, prepare the silicon slurry with p type and n N-type semiconductor N, the fusing spraying also is sintered to the substrate surface, silicon slurry sinter layer infiltrates through 1～2 micron of substrate, forms very firm silicon thin film, prepares p-n knot; Prepare metal electrode again, solar cell is made in encapsulation.

P-n knot is the primary structure unit of solar cell, utilizes this technology that p type, n N-type semiconductor N material are combined, and has just formed p-n knot in both junctions.It is physics barrel plating sintering rather than chemical deposition that the maximum characteristics of novel solar cell fabrication process of the present invention are to prepare p-n knot mode, pass through high temperature, utilize the physical bond characteristic that silicon is starched evenly and permeated and be sintered in substrate material surface, owing to use the physics barrel plating, so not having chemical waste fluid pollutes, manufacture craft is simple relatively, compare chemical deposition process in the past, under lower-cost situation, can improve the production efficiency of solar cell rapidly, reduce investment threshold, and the mating surface treatment process can guarantee battery conversion efficiency.And can be applied to monocrystalline silicon, polysilicon, banded silicon and thin-film material (comprising microcrystalline silicon film, compound-base film and dye film) battery process.

Improving conversion efficiency and reducing cost is two principal elements considering in the solar cell preparation, for present silicon is solar cell, because crystalline silicon is indirect bandgap semiconductor material, the desired light photoelectric transformation efficiency of its battery is slightly larger than 30%, the laboratory has reached 25% at present, the conversion efficiency of solar cell of industrial mass manufacture is generally 10% to 17%, and wanting further to improve conversion efficiency is the comparison difficulty again.Reducing production costs as far as possible under the prerequisite that guarantees conversion efficiency is effective breach, and the present invention prepares p-n junction and adopts physics barrel plating sintering effectively to reduce cost, and possesses very strong Market and Technology demand and operation prospect.

Above-described sintering barrel plating technology also may be applicable to the manufacturing of other types, and this is understandable.The present invention has been carried out concrete elaboration by foregoing, repeats no more herein.But should be noted that.Adjustment, modification and the additions and deletions that any technical staff is done on form and details this technology all be unable to do without the marrow of the present invention.

Technical field

The present invention is a technology that adopts physics barrel plating sintering to carry out surface coating, be applicable to various need being particularly useful in monocrystalline silicon, polysilicon, banded silicon and thin-film material (comprising microcrystalline silicon film, compound-base film and the dye film) battery process in the flow process of substrate surface deposition.

Background technology

Abundant solar radiant energy is important green energy resource, is the energy inexhaustible, nexhaustible, pollution-free, that the mankind can freely utilize.Solar energy arrives the energy on ground each second up to 800,000 kilowatts, if the solar energy of earth surface 0.1% is transferred to electric energy, number turnover 5%, annual energy output are equivalent to 40 times of present energy consumption in the world.When non-renewable energy resources such as electric power, coal, oil signal for help repeatedly, when energy problem became the bottleneck of restriction international community economic development day by day, more and more countries began to develop solar energy resources, seeks the new power of economic development.Under the promotion of international photovoltaic market great potential, the solar cell manufacturing industry of various countries falls over each other to drop into huge fund, enlarges to produce, to strive one seat.World manufacture of solar cells enterprise aggregated capacity reached more than the 1000MW in 2004, increased by 35% on a year-on-year basis.2005, world solar cell total output 1656MW, wherein Japan still ranks first, and 762MW accounts for 46% of Gross World Product, and Europe is 464MW, accounts for 28% of total output, and U.S. 156MW accounts for 9% of total output, and other 274MW account for 17% of total output.

Compare with flourish in the world photovoltaic generation, China lags behind the 10-15 of developed country, even lags significantly behind India.But, China's photovoltaic industry is just with annual 30% speed increment, Chinese manufacture of solar cells total amount reached 139MW in 2005, increased sharply 179% than 2004, reached 400MW in 2006, become global the third-largest producing country thereby surpass the U.S., production capacity then reaches surprising 1180MW, becomes the fastest country of global evolution.

In the evolution of solar cell, polycrystal silicon cell becomes main flow, the preparation silicon fiml is a very important step in its production process, traditional process adopts chemical vapour deposition technique on being 1～3 centimetre silicon materials substrate at thickness, low-pressure chemical vapor deposition (LPCVD) for example, plasma reinforced chemical vapour deposition (PECVD), liquid phase epitaxial method (LPE) etc., its mechanism is that substrate is heated to about 1000 degrees centigrade, utilize silane (SiH4), the thermal decomposition of trichlorosilane gases such as (SiHCl3), generate silicon atom, and be deposited on substrate surface, during reaction, feed borine simultaneously, form the p type silicon thin film of boron-doping, but Zhi Bei silicon thin film is amorphous state mostly like this, needs by solidifying crystallization, technology such as district's clinkering crystalline substance and laser crystallization, with noncrystalline membrane remelting crystallization again, finally form polysilicon membrane.The major defect of chemical vapour deposition technique is: the depositing operation complexity, the cost height especially needs a large amount of market silicon substrate material in short supply, consumes a large amount of chemical liquids, and contaminated environment.

Along with the fast development of solar energy industry, and Chinese pay attention to day by day protection environment, realizing sustainable development, market demand is a kind of can protect environment, and energy savings is simplified technological process, reduces cost, and especially saves the novel manufacturing process of silicon materials.

Good effect of the present invention is as follows: physics barrel plating sintering carries out the technology that plated film is a kind of simple and effective, with the chemical deposition mode that in the past adopted relatively, this novel process flow process that can simplify the operation reduces running cost, enhances productivity and environmental protection.

Should find out that simultaneously this invention is not limited to solar cell plated film industry, what other branchs of industry were required carries out plated film to substrate, also can use technology of the present invention.

The novel feature of the present invention is set forth in the above description.If but, then can more deep understanding be arranged to structure, method of operation, annex and the advantage of this invention in conjunction with the analysis of attached chart.

Description of drawings:

Accompanying drawing 1, solar cell fabrication process structural representation of the present invention; Existing market silicon materials in short supply are saved in the be altogether unjustifiable introducing of silicon substrate material in a large number, reduce production costs;

Accompanying drawing 2, solar cell fabrication process flow chart of the present invention;

Accompanying drawing 3, solar cell preparation principle and mechanism of power generation;

Claims

1, the preparation technology of this novel thin film solar cell comprises following key step:

Clean silicon materials, prepare the n N-type semiconductor N, add III family element and prepare the p N-type semiconductor N by adding V group element;

Under high temperature (temperature is higher than about 1410 degrees centigrade of silicon fusing points) condition, prepare the silicon slurry with p type and n N-type semiconductor N, the fusing spraying also is sintered to the substrate surface, preparation p-n knot;

With NaOH or KOH about 80 to 90 degrees centigrade, in silicon face making herbs into wool;

Preparation antireflective coating and metal electrode are made thin-film solar cells.

2, method according to claim 1, its silicon slurry that is used for spray sintering can be cut into the silica flour preparation by silicon materials (for example silico briquette, silicon chip etc.).

3, method according to claim 1 is characterized in that using physical method at high temperature p knot and n knot physics barrel plating to be carried out sintering in substrate material surface; Silicon thin film infiltrates about 1～2 micron of backing material behind the sintering, forms quite firm sinter layer; The degree of depth of sintering should satisfy firm requirement and guarantee the photoelectric conversion efficiency of p-n junction, as infiltrating distance greater than 2 microns, also belongs to the category of this sintering infiltration method.

4, method according to claim 3, its backing material is an exotic material, and can use the large tracts of land material, improves the light-receiving area of solar cell; That its shape can adopt is square, rectangle or circle etc.

5, method according to claim 3 can go out the multilayer p-n junction at folded knot high annealing, to improve photoelectric conversion efficiency after sintering goes out p-n junction.

6, method according to claim 3, its sintering can be at a slice backing material last layer one deck accumulation sintering; Also can be at a slice substrate surface sintering p knot film, another sheet substrate surface sintering n ties film, and then the p knot of two block of material is tied to contact with n and carry out the high annealing sintering, thus the preparation p-n junction; Other coating methods that under the thinking of physics barrel plating sintering the step of sintering carried out practical combinations also belong to the method protection category.

7, backing material according to claim 4, can before the sintering p-n junction, carry out process of surface treatment, as adopt high temp glass as backing material, then can carry out the surface etch of hydrofluoric acid, increase the suede effect on surface, prolonging light, and then improve photoelectric conversion efficiency in the time of break-through and the path of p-n junction.

8, method according to claim 1, it is characterized in that behind the sintering p-n junction, preparing conductive electrode, electrode needs sealing, the method for preparing electrode is: evenly (for example equidistant intervals) punching before barrel plating sintering p-n junction, directly draw conductive electrode after waiting to finish the p-n sintering from the conducting film side.

9, method according to claim 1, its backing material, p-n junction shape and sintering annealing steps carry out local modification according to required technology, also should belong in this novel thin film preparation method of solar battery.